Puerto Rico sets the stage for microgrids

As this year’s hurricane season bears down on Puerto Rico, people are bracing for more power outages, while holding out hope that new microgrids will be built to fortify the island and people's access to electricity.

The Puerto Rico Energy Commission a few weeks ago adopted a final microgrid regulation (PDF) to help drive development of the resilience technology.

The move was widely applauded by the renewable energy and next-generation power technology industries. Now, the question is how long will it take for investment to flow to Puerto Rico to build more microgrids.

"I’m seeing signs that investment might be available," said PJ Wilson, president of the Solar and Energy Storage Association of Puerto Rico. "People have come to me and said, ‘I have hundreds of millions of dollars of investment funds to build microgrids in Puerto Rico.’ Now that the microgrid rules are out, there’s literally nothing in the way of that happening."

Now that the microgrid rules are out, there’s literally nothing in the way of building microgrids in Puerto Rico.

A microgrid is a local power grid with control capability that allows it to disconnect from the traditional grid and operate autonomously.

Puerto Rico needs advanced microgrids to ensure that communities have electricity after a big storm, power technology experts say. Electricity systems that are decentralized and can operate independently of the central power grid can continue to provide backup power, even when the grid goes down, when switched to "island mode," which means they are disconnected from the grid and operating in a self-contained manner. Solar panels backed with batteries are popular microgrid resources, but such systems can be powered by just about any generator.

"One of the most perplexing challenges facing this promising market is figuring out how to steer private investment towards projects that offer the greatest value," Peter Asmus, research director at Navigant Research, said. "The ideal resource mix for regions challenged by hurricanes remains an open question. Nevertheless, I do believe this regulation is one of the most comprehensive approaches to microgrid development put forward and may serve as a model for other countries looking to scale up microgrids."

Microgrid technology is often viewed as a high-cost luxury for universities, corporate campuses and others who can afford it. But as prices for solar panels and batteries fall, and when compared with the cost of frequent and lengthy power outages, microgrids make economic sense in Puerto Rico.

One reason: Despite a $3.8 billion federal effort to repair the island’s severely damaged power grid after the devastation of Hurricane Maria in September, the electrical system is weak and vulnerable to more blackouts from one or more less powerful storms than Maria, Puerto Rican officials say.

Despite a $3.8 billion federal effort to repair the island’s severely damaged power grid, the electrical system is vulnerable to more blackouts from less powerful storms.

"It’s a highly fragile and vulnerable system that really could suffer worse damage than it suffered with Maria in the face of another natural catastrophe," Puerto Rican Gov. Ricardo Rossello said, according to a report by The Associated Press.

More than 10,000 homes and businesses are still without power, more than eight months after Maria, according to the federal government.

The National Oceanic and Atmospheric Administration is predicting a 70 percent chance that this year’s Atlantic hurricane season, which started June 1, will produce as many as nine hurricanes, up to four of which could be major, where winds can exceed 110 miles per hour.

AES Corporation — which operates a 510-megawatt coal plant and 24-megawatt solar farm in Puerto Rico, but also develops renewable energy and storage-backed microgrids in Hawaii, California and other locations — has proposed reorganizing Puerto Rico's grid (PDF) into a network of regional "mini-grids," which essentially would be large microgrids that could serve several towns, and one that could serve the city of San Juan. Solar power, which costs roughly $45 to $50 a megawatt-hour to build and operate on the island, could serve much, if not most, of the island's power needs, AES argued. That compares to $150 a megawatt-hour to operate the island's aging oil-fueled power plants.

Clean-energy microgrid providers have been building systems on the island since the hurricanes, primarily as part of the ongoing humanitarian assistance effort.

Sonnen has installed 11 solar-plus-storage microgrids in Puerto Rico with local solar partner Pura Energia at community centers, schools and a healthcare clinic. It’s the same technology and equipment that the company sells to customers in California, Europe and Australia, but used for heavy off-grid power generation and use, rather than as a resource that is interconnected to the grid.

"We’re focusing on that idea of using this as the center of something to build a community and as a tool to provide services to people who can’t get them elsewhere," Adam Gentner, Sonnen's director of business development, Latin American expansion, said.

During a blackout in April, the lights stayed on at a community center in Humacao, where Sonnen installed a microgrid.

Battery maker Blue Planet Energy also has installed solar-plus-storage microgrids in Puerto Rico, at a water-pumping station in the village of Corozal and at an apartment complex in Isabela that houses volunteers.

"The grid there is still quite unreliable even where it has been restored," Blue Planet Energy Chief Operating Officer Chris Johnson said. "A lot of people are saying, ‘I’m going to be grid independent and when the grid stabilizes, I can choose whether to reconnect."

The grid there is still quite unreliable, even where it has been restored.

The effects of Hurricane Maria led to estimated 4,645 deaths in Puerto Rico, according to a recent study published in the New England Journal of Medicine. One-third of the deaths were attributed to delayed or interrupted health care.

Puerto Rican households went 84 days without electricity, on average, 68 days without water and 41 days without cellular telephone coverage from after the hurricane until Dec. 31. In remote areas, 83 percent of households remained without electricity through the end of December, according to the report.